• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/44

Click to flip

44 Cards in this Set

  • Front
  • Back
ipRGCs
-intrinsically photosensitive retinal ganglion cells
-small percentage of ganglion cells
-contain melanopsin a photopigment which allows them to respond directly to light
-less sesnsitive to light than rods and cones bc of low pigment density
-response to light is depolarization
-non-image forming vision and participate in pupillary light reflex and circadian rhythms
What can rod cells do that cones cannot?
-detect dim light
Axons from optic tract to superior colliculus
-participates in reflex orienting the head in response to visual or other stimuli
-these projections might explain phenomenon of "blind sight"
axons from optic tract to hypothalamus
-projections to suprachiasmatic nucleus of hypothalamus
-probably act to train biological clock
axons from optic tract to pretectal area
-at junction of midbrain and diencephalon
-pretectal neurons project to edinger-westphal nucleus
-participate in pupillary light reflex
Where do the frontal eye fields project to?
-superior colliculus
-caudate nucleus
-horizontal and vertical gaze centers
Where are the frontal eye fields located?
Brodmann's area 8 in frontal lobe
Where do the frontal eye fields receive input from?
-from primary and association areas of visual cortex, supplementary eye feilds, dorsolateral prefrontal cortex, and auditory and somatosensory association areas
retinal disparity
-target not on fovea of both eyes
retinal blur
target out of focus
What area of the brain are jacksonian seizures associated with?
primary motor cortex
What are electrical stimulations of the premotor cortex associated with?
-more complex movements than primary motor cortex
-coordinated contractions over more than one joint
-orientation of body for upcoming movement and initiation of movement especially movements related to external stimuli
What area of the brain is associated with internally generated movements often involving both sides of the body?
-supplementary motor area
Electrical stimulation of the supplementary motor area will produce what?
-vocalization or complex postural movements
-movements involving bilateral muscle groups
How are the frontal eye fields involved in coordinating eye movements?
-triggers saccadic movement
-participates in coordinating smooth pursuit movements
What tract has some fibers ending on dorsal gray matter and ventral and intermediate gray?
corticospinal tract
3 sources of input for the reticulospinal tract?
1)basal ganglia
2)motor cortex
3)somatosensory cortex
Where does the reticulospinal tract originate in?
pontine and medullary reticular formation
What tract is responsible for complex reflexes (yawning, suckling orienting)
reticulospinal tract
indirect ascending pathway
the way the basal ganglia exerts motor control.
-modifies which descending cerebral output to motoneurons
What part of the basal ganglia controls saccadic eye movements?
-caudate
Parkinsons is produced by the loss of which tract?
-nigrostriatal dopaminergic tract
describe problems in the basal ganglia associated with parkinson's disease
-loss of nigrostriatal dopaminergic tract reduces inhibitory output of the striatal neurons on GPi resulting in greater inibition of thalamus
-less inhibitory sriatal output to GPe producing a disinhibition of the subthalamic nucleus and thereby inhibition of thalamic output
levodopa
-treatment for parkinsons
-precursor for DA synthesis
-passes blood brain barrier
-probably taken up by remaining dopaminergic neurons
anticholinergics to treat parkinsons
-used to be most effective
-with loss of nigrostriatal neurons cholinergic interneuons in striatum become more actitive
pallidotomy
-treatment for parkinsons
-lesion of GPi to decrease output
Describe huntington's disease
-loss of striatal GABA-ergic neurons which project to GPe but later there is also a loss in cholinergic interneurons from the stiatum
-loss of GABA-ergic = release of GPe from inhibitory influence
-GPe inhibits output of subthalamus nucleus resulting in reduced stimulation of GPi which causes reduction in thalamic inhibition by GPi and increase in cortical output
what secretes endolymph?
stria vascularis
Scala vestibuli
-chamber which oval window transmits vibrations
-contains perilymph
-separated from scala media by vesitbular membrane (reissner's membrane)
Scala media
-contains sense organ for earing (organ of corti)
-contains endolymph
-basilar membrane supports organ of corti and separates scala media from scala tympani
Scala tympani
-continuous with the scala vestibuli via the heliotrema
-contains perilymph
-contains the round window
Which has a high spatial resolution M or P?
P cells
What reflex is involved in matching target and eye velocity and keep object of interest on fovea?
smooth pursuit
Does saccadic eye movement require a target?
no
Saccades
-can be voluntary or reflex
-very accurate
-vision is lost during saccade (velocity is about 700 degrees/sec. Identical to fast phase of nystagmus)
-involvement of superior colliculus
Describe the involvement of the superior colliculus in saccades?
-sensory and motor maps
-maps are linked: a certain location in the s. colliculus = a point in space
-projects to gaze centers
-cerebellum controls gain
Function of interposed?
-correction of actual movement
basic functions of the cerebellum
- equilibrium and control of eye movements (control the gain of saccades)
-control of rapid, coordinated muscle movement
-execute sequential movements
-compare actual and intended movements and correction
-posture
-motor learning
What happens if you damage your olive or flocculonodule node?
-cannot make adjustments of motor movements
Describe receptor potentials
-graded response- amplitude of receptor potential increased with increasing stimulus intensity over a wide range
-decremental conduction
generator potential
-a specific type of receptor potential involving the depolarization of primary sensory endings produced by a stimulus. Leads to APs in the primary afferent fiber if depolarizations are large enough.
Knee jerk reflex
-AP in Ia produce monosynaptic excitation of alpha-motorneurons
-reciprocal innervation
-y-mototneurons maintain tension of intrafusal fibers and sensitivity of extrafusal
-co-activation of alpha and gamma motoneurons
inverse stretch reflex
-Golgi tendon organ receptor
-reports MUSCLE TENSION
-group Ib fibers inbibit A(alpha) and excite antagonistic muscle
Does opiate induced analgesia has a direct actions on ______
CNS (not on peripheral receptors)